I know half of the members will disagree with the concept of rear fill but here goes...

I was thinking of adding midbass to my rear deck. My bottom end is great (alpine MRP M650 400 watts rms and kicker 12" sub), and my soundstage is nice and detailed (Clarion 4x60 amp, energy 6.5" components up front). But I feel midbass is lacking somewhat. I'm planning on deadening the doors eventually (which I'm sure will help), but I have some questions about adding midbass drivers in the rear, using my remaining 2x60 clarion channels...just exploring here.

1. dedicated midbass drivers, like these kickers,

http://www.crutchfield.com/App/Product/Item/Main.aspx?search=midbass&i=2064SSMB8

How do you isolate the midbass frequencies? I have a choice on my amp of HiPass OR LoPass. Would I would choose LoPass under about 200 Hz, and let them try to deal with the Sub-bass frequencies? Or do they come with some sort of crossover or filter built in? I notice that some dedicated midbass drivers come with a separate filter, like these...

http://www.sonicelectronix.com/item_13945_MB+Quart+PVI164.html

the low pass filter seems to be preset at 250 Hz. But wouldn't you also want to filter out sub-bass as well, in order for them to be truly dedicated mid-bass? I'm assuming sending them sub 50 Hz frequencies would make them prone to distortion, defeat the purpose of a dedicated sub, and also require much more power than I have...
I also see higher end midbass drivers that don't appear to have any filters or crossovers...are we getting into the realm of outboard, digital processing (sry, I don't even know the terminology here) in order to split up and customize the spectrum like this?

2. Also, if one were to come across a couple of woofers from a good component system, how would they compare to the "dedicated" midbass type drivers? (Assuming proper filtering on them)

Thanks in advance guys for any input! Sorry for my noobishness. And sry bout the links...the site won't allow me direct URL links yet.

 

IMO you could probably do better, if you bridge that amp to 2 channels, and really feed those front components, and make sure you do deaden the doors. Also, try highpassing the fronts at 80hz, or lower if they can take it. Your amp prolly has 12db slope, and I think 70 hz would be ok, unless you have no variable xover option.

If you decide you want rear fill...and I do not think that amp has bandpass freq option...

GlassWolf's Homepage
^^^ click on this link

I do not recommend running midbass freq(<300) at the rear, as your sound stage may or may not suffer, but mainly you may generate more rattles on rear deck.

p.s. I really do not think you can get much midbass on 60 watts/side. So, I would strongly urge you to bridge that amp, and go that way. Way better than your rear fill option. You can thank me later

 

BTW, thats quiet a NICK you got there...

 

thank you Sasha, I would really like to try that.

So how do I bridge to 2 stereo channels? I was thinking about this and a bit confused. bridging 2 stereos results in a mono signal. So how to get stereo?
do i run front right and rear right from the HU to amps frontstage bridged and use that to drive the right channel up front? and the same configuration for the left channel? (Left front and left rear from HU to rear frontstage bridged, driving the left speaker).

or am I making a fool of myself here?

 

To get bridged left and bridged right, just feed the two channels that will become your left with two left RCAs and the two right channels with right RCAs.

Rear midbass is not completely unheard of but it takes more power and processing than you want to get into.

 

thank you Dukk, much more simply put. But I had the right idea.

 

A pair of the right speakers in the back with 60 watts each should be more then enough to add some serious midbass... check out the tangband 6.5 subwoofers at parts express or consider adding some 8's..... just low pass it....

hell even some pyramid 6x9s would add some loud *** midbass.... and on your caliber of system.. would do just fine...

 

Any mid-bass drivers you put in your rear deck (or any other speaker for that matter) when you have serious bass in the truck will either:

1) become a radiator for output energy from the subs and become effectively useless unless you isolate them with a rigid enclosure. Or worse, have a 6.5" nuked by the 12" subs directly underneath.

2) if crossed over too high will pull your staging way back as they start to suffer from point-source loaclization.

It takes a hell of alot of processing to integrate a 3-way front end properly (I know, I've owned the best processing available), let alone worry about moving drivers to the back. If you have to use simple 2nd order crossover slopes, keep the mid-bass up front, by whatever means necessary.